Rocket Activity
Project X-51
Objective
To apply rocket principles and design,
construct, test, and launch a water rocket using
a real-world problem-solving simulation.
Description
National Science Content Standards
Unifying Concepts and Processes
• Evidence, models, and explanation
• Change, constancy, and measurement
Science as Inquiry
• Abilities necessary to do scientific
inquiry
Physical Science
• Position and motion of objects
• Motions and forces
Science and Technology
• Abilities of technological design
Science in Personal and Social Perspectives
• Risks and benefits
• Science and technology in local
challenges
National Mathematics Content Standards
• Number and Operations
• Geometry
• Measurement
• Data Analysis and Probability
National Mathematics Process Standards
• Problem Solving
• Reasoning and Proof
• Communication
• Connections
• Representations
Teams of students will form rocket companies
and compete in a commercial endeavor
to construct rockets capable of launching
payloads, astronaut crews, and even space
tourists to Earth orbit. Through a strong
interdisciplinary approach, balancing science
with technology, engineering, and mathematics,
Materials
(All supplies need to be available for each
group.)
• 2-liter soft drink bottle
• 1-liter water bottle
• 1 1” long by 3/4” diameter PVC segment
• Aluminum soft drink can
• Scrap cardboard, poster board, and tag
board
• Large cardboard panels (about 3X1 feet)
for silhouettes
• Duct tape
• Masking tape
• Glue stick
• Low-temperature glue gun
• Modeling clay
• Plastic grocery bag or garbage bag
• String
• Art supplies
(The following are needed for launch day.)
• Water rocket launcher (see page 109)
• Eye protection
• Altitude tracker (see page 80)
• Tape measure
• Water
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they will develop a budget, purchase
construction materials, and track expenditures
while designing and constructing their rocket.
They will then have to test the rocket for
stability and fill out specification sheets. Finally,
the teams will launch their rockets and conduct
a cost/benefit (altitude vs. cost) ratio.
Management
Prior to this project students should have the
opportunity to design, construct, and launch
water rockets using different water volumes and
pressures to see the effect these variables have
on the altitude. Students should also become
proficient in altitude tracking. (See article
on page 141.) Doing so will prepare them to
employ Newton’s laws of motion to maximize
the flight properties of their rockets.
Divide your students into teams of three.
They will form competing rocket companies in
a request for proposal, issued by NASA. Their
objective is to construct the best payload/crew/
space tourist orbital transport rocket. The
team will select roles for each member: Project
Manager, Budget Director, and Design and
Launch Director. One of the student pages that
follows contains badges for each student. The
back side of the badges explain the duties for
each job. Take digital head shot pictures of
each student and print them. Have students
trim the pictures and paste them on to their
badges prior to laminating them.
The project takes approximately two
weeks to complete and includes a daily
schedule of tasks. Students may need
additional time to complete daily tasks and
keep on schedule.
Collect all building materials and copy
all reproducibles before beginning the activity.
Make several copies of the order forms and
blank checks for each group.
Allow enough time on the first day for
students to read and discuss all sheets and
determine how the sheets apply to the project
schedule. Focus on the student score sheet
to make sure students understand the criteria
used to assess their performance.
By the end of the first day, teams should
have decided on the roles each member will
play, the name of the company, and started
their rocket design.
Background
From the beginning of the space program,
rockets, spacecraft, spacesuits, launch
platforms, and much more have been built by
contractors. The responsibility of the National
Aeronautics and Space Administration has been
to manage the exploration of the atmosphere
and space. When a particular space mission
is decided upon, requests for proposals are
issued to American industry to build the
hardware. Corporate teams propose designs
for rockets, space capsules, or whatever else
NASA needs for its mission. After a competitive
process, the winning corporation is chosen and
money is awarded to begin construction. Often,
when very large contracts are awarded, the
winning companies will select other companies
as subcontractors to build component
systems. This contracting strategy has worked
successfully for NASA for more than 50 years.
Now, NASA is looking to promote
new space industries with the capabilities of
constructing, launching, and controlling their
own rockets. NASA looks forward to contracting
with these companies to transport supplies
and crew to the International Space Station,
permitting NASA to concentrate on the large
missions that will push outward the frontiers of
space.
Procedure
Refer to the student sheets and the project
schedule for details on specific tasks and
when they should be performed. The project
schedule calls for teacher demonstration on
how to make nose cones on day 3 and how to
determine the center of pressure and center of
mass on day 6.
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Discussion
• What did you learn about running a company?
How might you have done things differently?
What was the most difficult part of the two
weeks? What do you understand now that
you were not sure or aware of before?
• Why is NASA supporting the development of
private launch vehicles?
Assessment
Base the assessment of team performance
on their documentation: Project Journal,
Silhouette, and Launch Results. Refer to the
Project X-51 Score Sheet for details.
Extensions
• Large space missions often require a wide
range of subcontractors across the United
States to provide the expertise needed
to build the launch and vehicle systems.
Learn about the contributions contractors
in your state make towards the exploration
of outer space. A good place to start is
with the Space Grant Consortium for your
state. Consortium members (colleges and
universities) promote space research and
educational activities in their home states
and work with local space industries. The
following website contains an interactive
listing of Space Grant programs by state:
http://www.nasa.gov/offices/education/
programs/national/spacegrant/home/Space_
Grant_Directors.html
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Rocket Stability Determination
(Swing Test)
A rocket that flies straight through the air is said
to be stable. A rocket that veers off course
or tumbles is said to be unstable. Whether a
rocket is stable or unstable depends upon its
design.
All rockets have two “centers.” The first
is the center of mass. This is a point about
which the rocket balances. The picture to the
right shows a rocket suspended from a string.
The rocket is hanging horizontal. That means
that it is balanced. The string is positioned
exactly beneath the rocket’s center of mass.
(This rocket looks like it should really hang with
its tail section downward. What you can’t see
in the picture is a mass of clay placed in the
rocket’s nose cone. This gives the left side as
much mass as the right side. Hence, the rocket
balances.)
The center of mass is important to a
rocket. If the rocket is unstable, it will tumble
around the center of mass in flight the way a
stick tumbles when you toss it.
The other “center” of a rocket is the
center of pressure. This is a point in the shape
of the rocket where half of the surface area of
the rocket is on one side and half on the other.
The center of pressure is different from the
center of mass in that its position is not affected
by what is inside the rocket. It is only based on
the rocket’s shape.
Air strikes the surface of the rocket as
the rocket moves. You know what this is like.
If you stick your arm outside a car window
when it is moving, you feel pressure from the
air striking your arm. The center of pressure of
a rocket is the middle point. Half of the total
pressure on the rocket is on one side of the
point and half on the other.
Depending upon the design of the
rocket, the center of mass and the center of
pressure can be in different places. When
the center of mass is in front of the center of
pressure (towards the nose end), the rocket is
stable. When the center of pressure is towards
the front, the rocket is unstable.
When designing a stable rocket, the center
of mass must be to the front and the center
of pressure must be to the rear.
A simple way to accomplish stability is
to place fins at the rear of the rocket and place
extra mass in the nose. Look at the rockets
below. One of them is stable and the others are
not. The center of mass is shown with a back
dot. The center of pressure is shown with a red
dot. Which rocket will fly on course?
Rocket B is the most stable rocket. Rocket
C will definitely tumble in flight. Rocket A will
probably fly on a crooked path. Any cross
winds encountered by the rocket as it climbs
will cause it to go off course.
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How to Determine Your Rocket’s Stability
1. Draw a scale diagram of your rocket on the
graph paper. Make it exactly like the shape
of your rocket as seen from the side.
2. Tie a string loop snugly around your rocket
so that you have one long end to hold.
Except for the water needed for launch, your
rocket should be set up exactly as it will be
during launch.
2. Slide the loop until the rocket hangs
horizontally. When it hangs horizontally, the
string is at the rocket’s center of mass. Mark
that spot in the middle of your rocket on the
scale diagram. Use a black dot.
3. Cut out a silhouette of your rocket from a
piece of cardboard. Make it exactly the
same shape and size of your rocket as seen
from the side.
4. Balance the silhouette on the edge of a
ruler. The center of pressure of your rocket
is where the ruler is located. Mark that spot
in the middle of your rocket on the scale
diagram. Use a red dot.
5. If the center of pressure is before (towards
the rocket’s nose) the center of mass, add
some additional clay to the rocket OR
increase the size of the fins. Repeat the tests
until the center of mass is in front.
6. Verify your design results by conducting a
swing test. Balance the rocket again with the
string. Use a couple of pieces of masking
tape to hold the string loop in position.
7. Stand in a clear area and slowly start the
rocket swinging in a circle. If the rocket
is really stable, it will swing with its nose
forward and the tail to the back.
In flight, the rocket will try to tumble around
its center of mass. If the center of pressure
is properly placed, the rocket will fly straight
instead. More air pressure will be exerted on
the lower end of the rocket than on the upper
end. This keeps the lower end down and the
nose pointed up!
Swing Test
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Electrical Engineer
Environmental Scientist
Geographer
Geologist
Materials Engineer
Mechanical Engineer
Meteorologist
Mission Controller
Nurse
Oceanographer
Physicist
Public Affairs Specialist
Robotics Engineer
Safety and Occupational Health Specialist
Simulation Specialist
Teacher
Technician
Test Pilot
Wildlife Biologist
Current NASA Jobs — http://www.nasajobs.nasa.gov/
Student programs, microgravity flights, contests — http://www.nasajobs.nasa.gov/studentopps/employment/default.
People of NASA, who they are and what they do — http://quest.nasa.gov/about/index.html
Visit some of the Internet sites below. They list current NASA job openings, help future aerospace workers plan their education,
and tell about opportunities available to students. Also check out the opportunities available on the Internet sites of private
space companies that launch space tourists, satellites, and build heavy-lift rockets for transporting cargo to orbit.
NASA and the companies that build rockets and spacecraft are always on the lookout for future scientists, technicians,
engineers, and mathematicians. They need people who can plan, design, build, manage, and fly missions throughout the
Solar System. Big rockets and spacecraft are comprised of many integrated systems. People, working together, build
spacesuits, prepare space food, construct energy and environmental systems, program computers, and train flight crews.
Doctors keep the astronauts healthy on the ground and in space. Technicians prepare the launch pads, pack booster
parachutes, and process payloads.
See a job that looks interesting? Want to joint the team? All these careers and many more are needed to explore space.
Aerospace Engineer
Architect
Astronaut
Astronomer
Biologist
Chemical Engineer
Chemist
Communications Engineer
Computer Engineer
Dietician
Doctor
It Takes a Community to Explore Space
Print this page on the back of the achievement award.
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